I am not an energy Rater .. I am an architect

I am curious if any "Home Energy Pros" make an effort to locate the Neutral Pressure Plane (NPP) of a house that is being blower door tested?

Views: 4559

Reply to This

Replies to This Discussion

Don, I agree, I agree,

As for actually pointing to an elevation and saying the NPP is about here, somewhere in one of these posts I explained how to do that and it is rather easy.  All that is necessary is a ▲t and a manometer.  From inside and outside temperatures, a stack pressure per foot can be calculated.  Then, by taking a high or low pressure reading (that's where the pressure will be the largest) through the envelope, you have it.  If the front door reading is 2pa and you had calculated a 0.25pa per foot stack pressure, then the NPP is 8' above the penetration at the front door.

If you want to get fancy and you have a good ▲t, you can open a window a measured amount and, just like the "add a hole" process for pressure diagnostics, you can estimate the CFM50.  I keep baiting people with this in hopes that someone will do the math for me :).  My to-do list it too long.

As for the metal capillary tube, you can't get too small as a manometer does require a flow of air.  I would have to ask to be sure.  Just an FYI.

Bud

PS, I have started another thread to get into this issue a bit more: http://homeenergypros.lbl.gov/forum/topics/controlling-passive-air-...

RSS

Featured Forum Discussions

Too many BTU's. Too much horsepower?

Started by Steve in General Forum. Last reply by Eric Kjelshus on Saturday. 4 Replies

Stack/wind pressure and flow networks.

Started by Daniel James Grundy in Training. Last reply by Daniel James Grundy on Thursday. 5 Replies

BDT with vermiculite in hollow CMU walls?

Started by Brad Cook in General Forum. Last reply by John Nicholas on Thursday. 2 Replies

Videos

  • Add Videos
  • View All

Latest Activity

Profile IconMatt Ward and Lucifer Prescott joined Home Energy Pros
7 hours ago
Kent Mitchell replied to Rob Madden's discussion Energy auditing as a stand-alone business model...
"Swiftsure Energy has run as consultants, verifiers and raters for 8 years- we audit very few (about…"
9 hours ago
Horace Douglas Hunt, Jr. commented on Home Energy Magazine's blog post The Elephant in the Room
"poignant and timely story!"
12 hours ago
Horace Douglas Hunt, Jr. liked Home Energy Magazine's blog post The Elephant in the Room
12 hours ago
Home Energy Magazine's blog post was featured

The Elephant in the Room

Last week I attended the annual Home Performance Coalition (HPC) Conference & Trade Show in…See More
19 hours ago
Home Energy Magazine posted a blog post

The Elephant in the Room

Last week I attended the annual Home Performance Coalition (HPC) Conference & Trade Show in…See More
yesterday
Diane Chojnowski replied to Quinn Korzeniecki's discussion Don MacOdrum Receives BPI's 2017 Tony Woods Award and Four Others Inducted in to Hall of Fame in the group Building Performance Institute (BPI)
"Congratulations Mike! Thanks for all you do for the home performance industry!"
yesterday
Sarah OConnell's blog post was featured
yesterday

Home Energy Pros

Welcome to Home Energy Pros – the unique digital community by and for those who work in the home energy performance arena.

Home Energy Pros was founded by the developers of Home Energy Saver Pro (supported by the U.S. Department of Energy) and brought to you in partnership with Home Energy magazine.  Home Energy Pros is sponsored by the Better Buildings Residential Network. Please honor our Guidelines

© 2017   Created by Lawrence Berkeley National Laboratory.   Powered by

Badges  |  Report an Issue  |  Terms of Service